Tocilizumab relieves ICI-related arthritis, prevents relapse during rechallenge

The use of tocilizumab (TCZ) shows efficacy in the treatment and prevention of immune checkpoint inhibitor (ICI)-associated arthritis (AR) upon ICI rechallenge, according to a study.

“This dual efficacy of TCZ could significantly change the therapeutic landscape for patients undergoing ICI therapy who are at risk of, or have experienced, ICI-AR,” the researchers said. 

“By facilitating the broader use of ICIs in cancer patients, TCZ could ensure that a greater number of patients benefit from potent immunotherapy potentially improving patient outcomes by maintaining uninterrupted and effective ICI treatment,” they added.

Twenty-six patients with ICI-AR (median age 70 years) were included in the analysis. They received prednisone (CS) at 0.3 mg/kg tapered at 0.05 mg/kg weekly for 6 weeks, with TCZ 8 mg/kg administered every 2 weeks.

A subgroup of patients (n=11) received secondary prophylaxis during ICI rechallenge. TCZ was reintroduced with the same regimen together with ICI rechallenge, without CS. A control group (n=5) was also rechallenged but without TCZ.

The researchers assessed the TCZ efficacy in ICI-AR treatment and as secondary prophylaxis during ICI rechallenge. They also examined the postrechallenge evaluation of ICI duration, reintroduction of CS >0.1 mg/kg/day, ICI-AR flares, and disease control rate.

Over a median follow-up of 864 days from ICI initiation, all 20 patients (100 percent) treated with TCZ for ICI-AR achieved an ACR70 response rate, defined as >70 percent improvement, at 10 weeks. After 24 weeks of TCZ use, 81 percent achieved steroid-free remission. [Ann Oncol 2025;36:43-53]

In rechallenged patients, those receiving TCZ prophylaxis achieved a reduction in ICI-AR relapses over a median follow-up of 552 days when compared with patients who did not receive prophylaxis (17 percent vs 40 percent). The need for CS was completely eradicated with prophylaxis (0 percent vs 20 percent), with the mean duration of ICI treatment extended from 113 to 206 days.

At 12-month postrechallenge, the disease control rate was 77 percent. Furthermore, CXCL9 remained elevated during TCZ prophylaxis and did not decrease from concentration levels at ICI-AR onset.

“In addition to treating ICI-AR, TCZ demonstrated efficacy as a secondary prophylactic agent, preventing the recurrence of symptoms and lengthening ICI treatment duration after ICI rechallenge,” the researchers said.

Flares

The absence of arthritis flares or the need for CS during rechallenge when using TCZ as prophylaxis was another important finding of this study. Such an outcome addressed the challenge in managing patients with a history of ICI-AR.

“Typically, the recurrence of arthritis has constituted an obstacle to the continuation of potentially life-saving therapy,” the researchers said. “Our report underscores the efficacy of TCZ in preventing arthritis flares.”

These results suggest the benefits of combining TCZ with the arthritis treatment regimen at an early stage without interrupting ICI therapy.

In addition, the findings “set a new precedent for the management of ICI-AR and have the potential to significantly change current therapeutic paradigms by providing a more continuous and potentially more effective treatment pathway for patients undergoing ICI therapy,” according to the researchers.